2f:T40b,function createMapForPeriod(periodData, label) { return Plot.plot({ color: { type: "threshold", scheme: "YlGnBu", domain: activityBins }, projection: { type: zoneSettings.proj, rotate: zoneSettings.rot, domain: womarsSelected.data, inset: 10 }, marks: [ Plot.geo(land, { fill: "#ffffff", stroke: "black", strokeWidth: 0.5 }), Plot.graticule(), Plot.dot( periodData, Plot.hexbin( { fill: (g) => d3.max(g, (d) => d.activity) }, { x: "lon", y: "lat", fillOpacity: 0.9, symbol: "hexagon", stroke: "black", strokeWidth: 0.2, binWidth: 8 } ) ), Plot.geo(womarsSelected.data, { stroke: "#b10318", strokeWidth: 1.5, strokeDasharray: "5,3" }), Plot.sphere({ strokeWidth: 0.5 }) ], width: 450, height: 280 }); }30:T7c3,rows = timePeriods.map((period) => { let distPlot; const periodData = filterDataForPeriod(data, period.start, period.end); const correctedData = periodData .map((d) => ({ ...d, activity: correctDecay(d.activity, period.start, d.time) })) .filter((d) => d.activity != 0); // console.log(correctedData.filter((d) => d.activity == 0)); // Skip if no data for this period if (correctedData.length === 0) { return html`

No data available for ${period.label}

`; } const mapPlot = createMapForPeriod(correctedData, period.label); if (chartType == "Histogram") { distPlot = createHistogramForPeriod(correctedData, period.label); return html`

${period.label} (n=${periodData.length})

${mapPlot}

${distPlot}

`; } else { distPlot = createQQPlotForPeriod(correctedData, period.label); return html`

${period.label} (n=${periodData.length})

${mapPlot}

${distPlot}

`; } })31:Tbec,configWomarsZones = ({ 1: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 2: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 3: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 4: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 5: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 6: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 7: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 8: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 9: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 10: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 11: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 12: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 13: { timePeriods: defaultTimePeriods, proj: "azimuthal-equal-area", rot: [0, 90, 0] }, 14: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 15: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 16: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 17: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 18: { timePeriods: defaultTimePeriods, proj: "azimuthal-equal-area", rot: [0, -90, 0] }, 19: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 20: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 21: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 22: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 23: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 24: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 25: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 26: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 27: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 28: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 29: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles }, 30: { timePeriods: defaultTimePeriods, proj: defaultProj, rot: defaultEulerAngles } })32:[] 2d:{"title":"LaMer Visualization (in-progress)","cells":[{"id":0,"value":"# LaMer Visualization (in-progress)","pinned":false,"hidden":false,"mode":"md"},{"id":1579,"value":"## 1. Area of Interest","pinned":false,"hidden":false,"mode":"md"},{"id":1235,"value":"1. **Hover** over any [WOMARS (Worldwide MArine Radioactivity Studies)](https://www-pub.iaea.org/MTCD/Publications/PDF/TE_1429_web.pdf) zone to see its name and ID\n2. **Click** on a zone to select and view its data","pinned":false,"hidden":false,"mode":"md"},{"id":824,"value":"// WOMARS Latitudinal Boxes selector\nviewof womarsSelected = geoMarineSelector({\n geoData: womars_zones,\n fillAccessor: (d) => d.properties.id,\n labelAccessor: (d) => `Zone: ${d.properties.id}: ${d.properties.name}`,\n idAccessor: (d) => d.properties.id,\n width: 800\n})","pinned":false,"hidden":false,"mode":"ojs"},{"id":828,"value":"html`Selected WOMARS Zone: ${\n womarsSelected\n ? womarsSelected.data.properties.name.toUpperCase()\n : \"REQUIRED - PLEASE SELECT A ZONE\"\n}`","pinned":false,"hidden":false,"mode":"ojs"},{"id":1649,"value":"## 2. Seawater Sample Parameters","pinned":false,"hidden":false,"mode":"md"},{"id":1633,"value":"html`

\n ${viewof dateFrom}\n ${viewof dateTo}\n ${viewof rdn}\n ${viewof depth}\n

`","pinned":false,"hidden":false,"mode":"ojs"},{"id":256,"value":"## 3. Overall activity distribution","pinned":false,"hidden":false,"mode":"md"},{"id":241,"value":"Plot.plot({\n grid: true,\n x: {\n round: true,\n ticks: 10,\n transform: (d) => Math.pow(10, d),\n type: \"log\",\n tickFormat: \"~s\",\n label: `Activity in Bq/m3 (log scale) →`\n },\n y: {\n label: \"Proportion ↑\",\n tickFormat: \".0%\"\n },\n marks: [\n Plot.rectY(\n data,\n Plot.binX(\n { y: \"proportion\" },\n {\n x: (d) => Math.log10(d.activity || NaN),\n inset: 0,\n opacity: 1\n }\n )\n ),\n Plot.line(normalCurve(data), {\n x: \"x\",\n y: \"y\",\n // stroke: \"#e41a1c\",\n stroke: \"#ff7f00\",\n strokeWidth: 2,\n strokeDasharray: \"5,5\"\n })\n ],\n height: 200\n})","pinned":false,"hidden":false,"mode":"ojs"},{"id":261,"value":"## 4. Number of measurements over time","pinned":false,"hidden":false,"mode":"md"},{"id":258,"value":"Plot.plot({\n grid: true,\n y: {\n label: \"Count ↑\"\n // tickFormat: \".0%\"\n },\n marks: [\n Plot.rectY(data, Plot.binX({ y: \"count\" }, { x: \"time\", tip: true })),\n Plot.ruleY([0])\n ],\n height: 200\n})","pinned":false,"hidden":false,"mode":"ojs"},{"id":378,"value":"## 4. Activity over time","pinned":false,"hidden":false,"mode":"md"},{"id":380,"value":"hexTimeChart.legend(\"color\", {\n label: `Number of measurements`,\n width: 320,\n tickFormat: \"~s\"\n})","pinned":false,"hidden":false,"mode":"ojs"},{"id":375,"value":"hexTimeChart = Plot.plot({\n grid: true,\n color: { scheme: \"OrRd\" },\n y: {\n type: \"log\",\n tickFormat: \"~s\",\n inset: 6\n },\n marks: [\n Plot.dot(\n data,\n Plot.hexbin(\n { fill: \"count\" },\n {\n x: \"time\",\n y: \"activity\",\n symbol: \"hexagon\",\n fillOpacity: 0.9,\n stroke: \"black\",\n strokeWidth: 0.5,\n strokeOpacity: 0.5,\n binWidth: 7,\n tip: true\n }\n )\n )\n ]\n})","pinned":false,"hidden":false,"mode":"ojs"},{"id":267,"value":"### Time-Faceted Maps","pinned":false,"hidden":false,"mode":"md"},{"id":477,"value":"// feel free to adjust it\nactivityBins = [1, 20, 1000, 10000] ","pinned":false,"hidden":false,"mode":"ojs"},{"id":2736,"value":"viewof chartType = Inputs.select([\"Histogram\", \"Q–Q plot\"], {\n label: \"Dist. Chart Type: \",\n value: \"Histogram\"\n})","pinned":false,"hidden":false,"mode":"ojs"},{"id":2249,"value":"colorLegend = Plot.legend({\n color: {\n type: \"threshold\",\n scheme: \"YlGnBu\",\n domain: activityBins\n },\n label: \"Activity in Bq/m³\",\n width: 320,\n tickFormat: \"~s\"\n})","pinned":false,"hidden":false,"mode":"ojs"},{"id":2213,"value":"html`\n

\n ${rows}\n

`","pinned":false,"hidden":false,"mode":"ojs"},{"id":3077,"value":"### Data List of Selected Data","pinned":false,"hidden":false,"mode":"md"},{"id":3060,"value":"Inputs.table(data, {\n columns: [\"time\", \"activity\", \"depth\", \"refId\" ,\"source\", \"conversion\"],\n header: {\n time: \"Date/Time\",\n activity: \"Activity (Bq/m3)\",\n depth: \"Depth (m below sea level)\",\n ref: \"Ref ID\",\n source: \"Data Source\",\n conversion: \"Unit Conversion\"\n }\n})","pinned":false,"hidden":false,"mode":"ojs"},{"id":3079,"value":"___","pinned":false,"hidden":false,"mode":"md"},{"id":2228,"value":"timePeriods = timePeriod.slice(0, -1).map((start, i) => ({\n start,\n end: timePeriod[i + 1],\n label: `${formatDate(start)} to ${formatDate(timePeriod[i + 1])}`\n}))","pinned":false,"hidden":false,"mode":"ojs"},{"id":2204,"value":"function filterDataForPeriod(data, startDate, endDate) {\n return data.filter((d) => {\n const dataTime = new Date(d.time);\n return dataTime >= startDate && dataTime < endDate;\n });\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":2206,"value":"$2f","pinned":false,"hidden":false,"mode":"ojs"},{"id":2209,"value":"function createHistogramForPeriod(periodData, label) {\n return Plot.plot({\n grid: true,\n x: {\n round: true,\n ticks: 5,\n transform: (d) => Math.pow(10, d),\n type: \"log\",\n tickFormat: \"~s\",\n label: `Activity in Bq/m³ (log scale) →`\n },\n y: {\n label: \"Proportion ↑\",\n tickFormat: \".0%\"\n },\n marks: [\n Plot.rectY(\n periodData,\n Plot.binX(\n { y: \"proportion\" },\n {\n x: (d) => Math.log10(d.activity || NaN),\n inset: 0\n }\n )\n ),\n Plot.line(normalCurve(periodData), {\n x: \"x\",\n y: \"y\",\n stroke: \"#ff7f00\",\n strokeWidth: 2,\n strokeDasharray: \"5,5\"\n })\n ],\n width: 350,\n height: 280\n });\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":2725,"value":"function createQQPlotForPeriod(periodData, label) {\n const normalQs = getQuantiles(getNormalData(periodData));\n const dataQs = getQuantiles(periodData.map((d) => Math.log10(d.activity)));\n\n return Plot.plot({\n grid: true,\n x: { label: \"Theoretical Normal Quantiles\" },\n y: { label: \"Sample Quantiles (log-transformed)\" },\n marks: [\n Plot.dot(d3.zip(normalQs, dataQs), {\n x: (d) => d[0],\n y: (d) => d[1],\n fill: \"white\",\n strokeWidth: 0.8,\n stroke: \"black\",\n r: 3\n }),\n Plot.line(\n [\n [d3.min(normalQs), d3.min(normalQs)],\n [d3.max(normalQs), d3.max(normalQs)]\n ],\n {\n stroke: \"red\",\n strokeDasharray: \"5,5\"\n }\n )\n ],\n // aspectRatio: 1,\n width: 350,\n height: 280\n });\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":2211,"value":"$30","pinned":false,"hidden":false,"mode":"ojs"},{"id":1829,"value":"## UI Widgets","pinned":false,"hidden":false,"mode":"md"},{"id":1657,"value":"viewof dateFrom = Inputs.date({ label: \"From:\", value: \"1960-01-01\" })","pinned":true,"hidden":false,"mode":"ojs"},{"id":1660,"value":"viewof dateTo = Inputs.date({ label: \"To:\", value: new Date() })","pinned":true,"hidden":false,"mode":"ojs"},{"id":2388,"value":"viewof depth = Inputs.range([-1, d3.max(dataSelected, (d) => d.depth)], {\n value: 100,\n label: \"Depth (m):\",\n step: 1\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":2345,"value":"rdnOfInterest = _.pickBy(luts.nuclides, (value) =>\n [\"H-3\", \"Sr-90\", \"Cs-137\", \"Pu-239+Pu-240\"].includes(value)\n)","pinned":true,"hidden":false,"mode":"ojs"},{"id":1627,"value":"viewof rdn = Inputs.select(\n new Map(\n Object.entries(rdnOfInterest).map(([value, label]) => [label, +value])\n ),\n { label: \"Radionuclide:\", value: 33 }\n)","pinned":true,"hidden":false,"mode":"ojs"},{"id":1214,"value":"## Utils","pinned":false,"hidden":false,"mode":"md"},{"id":2876,"value":"function calculateBinWidth(logData) {\n const bin = d3.bin().thresholds(d3.thresholdScott);\n const bins = bin(logData);\n const min = d3.min(logData);\n const max = d3.max(logData);\n return bins[0].x1 - bins[0].x0;\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":2785,"value":"normalCurve = function (data) {\n const logData = data\n .map((d) => Math.log10(d.activity))\n .filter((d) => !isNaN(d));\n const mu = d3.mean(logData);\n const sigma = d3.deviation(logData);\n const minX = d3.min(logData);\n const maxX = d3.max(logData);\n const binWidth = calculateBinWidth(logData);\n\n return d3.range(minX, maxX, (maxX - minX) / 100).map((x) => ({\n x: x,\n y:\n binWidth *\n (1 / (sigma * Math.sqrt(2 * Math.PI))) *\n Math.exp(-0.5 * Math.pow((x - mu) / sigma, 2))\n }));\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":2729,"value":"formatDate = d3.timeFormat(\"%Y-%m-%d\")","pinned":true,"hidden":false,"mode":"ojs"},{"id":967,"value":"idSelectedZone = womarsSelected ? womarsSelected.zone : {}","pinned":true,"hidden":false,"mode":"ojs"},{"id":1088,"value":"defaultProj = \"equal-earth\"","pinned":true,"hidden":false,"mode":"ojs"},{"id":2319,"value":"defaultEulerAngles = [0, 0, 0]","pinned":true,"hidden":false,"mode":"ojs"},{"id":1062,"value":"$31","pinned":false,"hidden":false,"mode":"ojs"},{"id":1118,"value":"zoneSettings = configWomarsZones[idSelectedZone]","pinned":true,"hidden":false,"mode":"ojs"},{"id":1883,"value":"idSelectedZone","pinned":true,"hidden":false,"mode":"ojs"},{"id":1066,"value":"defaultTimePeriods = [\n \"1950-01-01\",\n \"1960-01-01\",\n \"1970-01-01\",\n \"1980-01-01\",\n \"1990-01-01\",\n \"2000-01-01\",\n \"2010-01-01\",\n \"2020-01-01\",\n \"2025-07-24\"\n]","pinned":true,"hidden":false,"mode":"ojs"},{"id":692,"value":"timeScale = (function (array) {\n const timeDomain = array.slice(1, -1);\n const timeRange = d3\n .pairs(array)\n .map((d) => `${timeFormatter(d[0])} - ${timeFormatter(d[1])}`);\n return d3.scaleThreshold().domain(timeDomain).range(timeRange);\n})(timePeriod)","pinned":true,"hidden":false,"mode":"ojs"},{"id":1161,"value":"timeFormatter = d3.timeFormat(\"%b %d, %Y\")","pinned":true,"hidden":false,"mode":"ojs"},{"id":1124,"value":"timePeriod = zoneSettings.timePeriods.map((d) => new Date(d))","pinned":true,"hidden":false,"mode":"ojs"},{"id":2431,"value":"### Decay correction","pinned":false,"hidden":false,"mode":"md"},{"id":2413,"value":"// In seconds\nhalfLifes = ({ 1: 388.5e6, 12: 908.8e6, 33: 947.3e6, 77: 207.04e9 })","pinned":true,"hidden":false,"mode":"ojs"},{"id":2491,"value":"correctDecay = function (activity, start, end, halfLife) {\n const decayConstant = Math.log(2) / halfLifes[rdn];\n const timeInterval = (end - start) / 1000;\n return activity * Math.exp(decayConstant * timeInterval);\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":2501,"value":"For instance:","pinned":false,"hidden":false,"mode":"md"},{"id":2497,"value":"correctDecay(2, new Date(\"2024-01-01\"), new Date())","pinned":true,"hidden":false,"mode":"ojs"},{"id":2533,"value":"### QQ plot","pinned":false,"hidden":false,"mode":"md"},{"id":2554,"value":"dataMean = d3.mean(data, (d) => Math.log10(d.activity))","pinned":true,"hidden":false,"mode":"ojs"},{"id":2666,"value":"numQuantiles = Math.min(data.length, 50)","pinned":true,"hidden":false,"mode":"ojs"},{"id":2556,"value":"dataStd = d3.deviation(data, (d) => Math.log10(d.activity))","pinned":true,"hidden":false,"mode":"ojs"},{"id":2697,"value":"getNormalData = function (data, n = data.length) {\n const mean = d3.mean(data, (d) => Math.log10(d.activity));\n const std = d3.deviation(data, (d) => Math.log10(d.activity));\n return Float64Array.from({ length: n }, d3.randomNormal(mean, std));\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":2702,"value":"getNormalData(data)","pinned":true,"hidden":false,"mode":"ojs"},{"id":2537,"value":"normalData = Float64Array.from(\n { length: data.length },\n d3.randomNormal(dataMean, dataStd)\n)","pinned":true,"hidden":false,"mode":"ojs"},{"id":2539,"value":"Plot.plot({\n height: 100,\n width: 250,\n marks: [\n Plot.rectY(getNormalData(data), Plot.binX({ y: \"count\" })),\n Plot.ruleY([0])\n ]\n})","pinned":false,"hidden":false,"mode":"ojs"},{"id":2593,"value":"Plot.plot({\n height: 100,\n width: 250,\n marks: [\n Plot.rectY(\n data.map((d) => Math.log(d.activity)),\n Plot.binX({ y: \"count\" })\n ),\n Plot.ruleY([0])\n ]\n})","pinned":false,"hidden":false,"mode":"ojs"},{"id":2564,"value":"getQuantiles = function (data) {\n const numQuantiles = Math.min(data.length, 50);\n const step = 1 / (numQuantiles + 1);\n const quantileValues = d3.range(step, 1, step);\n return quantileValues.map((d) => d3.quantile(data, d));\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":2568,"value":"normalQs = getQuantiles(getNormalData(data))","pinned":true,"hidden":false,"mode":"ojs"},{"id":2551,"value":"dataQs = getQuantiles(data.map((d) => Math.log10(d.activity)))","pinned":true,"hidden":false,"mode":"ojs"},{"id":2606,"value":"Plot.plot({\n marks: [\n Plot.dot(d3.zip(normalQs, dataQs), { x: (d) => d[0], y: (d) => d[1] })\n ]\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":1223,"value":"## Data loading","pinned":false,"hidden":false,"mode":"md"},{"id":1898,"value":"MARIS data are now also accessible via an API, for further details refer to: https://observablehq.com/@maris-iaea/api","pinned":false,"hidden":false,"mode":"md"},{"id":1901,"value":"params = ({\n sampleTypeId: 1,\n //nuclideId: rdn,\n //samplingDateFrom: d3.timeFormat(\"%Y-%m-%d\")(dateFrom),\n //samplingDateTo: d3.timeFormat(\"%Y-%m-%d\")(dateTo),\n shapeTypeId: 1,\n // unit: \"Bq/m3\" if we wanted to limit by unit this should be how it works, I think, but no effect\n // areaId: \"61 \"\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":1904,"value":"dataRaw = getMeasurementData(params)","pinned":true,"hidden":false,"mode":"ojs"},{"id":3040,"value":"// How many different data sources?\nnew Set(dataRaw.map((d) => d.displayText))","pinned":true,"hidden":false,"mode":"ojs"},{"id":2359,"value":"dataRaw[0]","pinned":true,"hidden":false,"mode":"ojs"},{"id":1964,"value":"dataSelected = dataRaw\n .map((d) => ({\n lat: d.latitude,\n lon: d.longitude,\n time: new Date(d.begPeriod),\n depth: d.sampleDepth,\n isDetected: d.detection,\n activity: convertActivity(d.activity, d.unitId),\n unit: d.unit,\n refId: d.refId,\n source: d.displayText,\n unit: \"Bq/m3\",\n conversion: traceConversion(d.activity, d.unitId)\n }))\n .filter((d) =>\n (d.unit === \"Bq/m3\" || d.unit === \"TU\") && womarsSelected\n ? turf.booleanPointInPolygon(\n turf.point([d.lon, d.lat]),\n womarsSelected.data\n )\n : true\n ) // trying to filter by unit but again failing ","pinned":true,"hidden":false,"mode":"ojs"},{"id":1971,"value":"The units are either `Bq/kg` or `Bq/m3`. All activity should be converted to `Bq/m3` by dividing `Bq/kg` activity by `1.025` and multiplying by `1000`. ","pinned":false,"hidden":false,"mode":"md"},{"id":3048,"value":"convertActivity = (activity, unitId) => {\n switch (unitId) {\n case 7:\n return activity * 119;\n case 3:\n return activity / 1.025 * 1000;\n default:\n return activity;\n }\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":3055,"value":"traceConversion = (activity, unitId) => {\n switch (unitId) {\n case 7:\n return \"TU -> Bq/m3\";\n case 3:\n return \"Bq/kg -> Bq/m3\";\n default:\n return \"\";\n }\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":230,"value":"Finally, let's select detected (`=`) activities only for now. In later tutorials, we will show how to account for measurements under detection level using estimators like Kaplan-Meier, ... as described by the [Assessment on statistical techniques\napplicable to the OSPAR Radioactive Substances Strategy 2010 – 2020](https://www.ospar.org/documents?v=48498) document for instance.","pinned":false,"hidden":false,"mode":"md"},{"id":236,"value":"data = dataSelected.filter((d) => d.isDetected === \"=\" && d.depth <= depth)","pinned":true,"hidden":false,"mode":"ojs"},{"id":281,"value":"world = (\n await fetch(\"https://cdn.jsdelivr.net/npm/world-atlas@2/land-50m.json\")\n).json()","pinned":true,"hidden":false,"mode":"ojs"},{"id":393,"value":"And convert it to [TopoJSON](https://www.wikiwand.com/fr/TopoJSON):","pinned":false,"hidden":false,"mode":"md"},{"id":283,"value":"land = topojson.feature(world, world.objects.land)","pinned":true,"hidden":false,"mode":"ojs"},{"id":363,"value":"## Imports","pinned":false,"hidden":false,"mode":"md"},{"id":1226,"value":"import { geoMarineSelector } from \"@francobollo/select\"","pinned":true,"hidden":false,"mode":"ojs"},{"id":1229,"value":"import { world_fao_zones, womars_zones } from \"@francobollo/marine-regions\"","pinned":true,"hidden":false,"mode":"ojs"},{"id":1258,"value":"import { getMeasurementData, luts } from \"@maris-iaea/api\"","pinned":true,"hidden":false,"mode":"ojs"},{"id":366,"value":"import {toc} from \"@mbostock/toc\"","pinned":true,"hidden":false,"mode":"ojs"},{"id":862,"value":"turf = require(\"@turf/turf@7.2.0\")","pinned":true,"hidden":false,"mode":"ojs"}],"files":"$W32","stdlib":"1","titling":"auto"}